With the development of communications technologies, an increasing number of intelligent applications, such as instant messaging software and the MicroBlog, are integrated on a user equipment. In the foregoing intelligent applications, in a transmission process of an RLC data packet of the user equipment, when receiving or not receiving an RLC data packet sent by an RLC AM entity sender, a radio link control (RLC for short) acknowledged mode (AM for short) entity receiver returns acknowledgment information, for example, acknowledgment (ACK for short) or negative acknowledgment (NACK for short).
However, in order to transmit the acknowledgment information corresponding to the RLC data packet, great signaling overhead is generated, for example, before downlink acknowledgment information is transmitted, signaling such as physical downlink control channel (PDCCH for short) scheduling information is generated. Before uplink acknowledgment information is transmitted, signaling such as a scheduling request (SR for short), a buffer status report (BSR for short), and PDCCH scheduling information is generated. This leads to a waste of transmission resources.